Lofunzo, I don't see your point. Who cares if they have a bad week, I'm talking roto where end of the year numbers are all that matter (besides the fact that even
if they gave gave up 1 or 2 runs in 6 innings that is still an ERA or 1.50 or 3.00 which will help your ERA

).
Anyways my 10 team league is in a pretty close race for ERA with the 2nd through 8th place ERAs as follows:
3.65
3.70
3.76
3.81
3.88
3.90
3.94
Saves 2nd through 9th:
72
68
66
58
57
47
46
45
Lets assume that you had Gagne and Looper versus Mesa and Looper on your team and see how it would affect you ranking.
Gagne+ Looper= .21 added to your ERA with 58 saves
Mesa + Looper= .36 added to your ERA with 43 saves
So with Gagne rather than Mesa a team could move up about 2-3 spots in ERA, 3-4 in saves, not to mention how it would positively affect your WHIP and K rate (especially important with innings limits).
So having Gagne versus Mesa in my league would have moved you up potentially 8-12 points quite easily. Making him very valuable in my mind.